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BIOLOGICAL AND ECOTOXICOLOGICAL CHARACTERISTICS OF TERRESTRIAL VERTEBRATE SPECIES RESIDING IN ESTUARIES

Clapper Rail Clapper Rail photo by Jim Zingo
(Photo by Jim Zingo)
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Biological Characteristics 

Species

Rallus longirostris is 32-41 cm in length. Mass ranges between 160 and 400 g. Males average 20% larger than females. Both sexes with grayish brown to cinnamon brown plumage, darker dorsally than ventrally. Flanks are barred white, dusky, and black. Base and sides of bill are pinkish to bright orange in males, duller in females (Edelman and Conway, 1998).

Status in Estuaries

A solitary ground nester, this species nests in salt, brackish, and freshwater marshes and mangrove swamps. A typical clutch would include 7-11 buff or olive-buff eggs in a basket-shaped nest of aquatic vegetation or tidal wrack, hidden on a firm bank or under a small bush. Young are precocial (Ehrlich et al., 1988). The maximum age of a clapper rail recorded in nature is 7 years, 6 months (Edelman and Conway, 1998).

Abundance and Range

The breeding range of the clapper rail on the east coast extends from New Hampshire south to the Florida Keys and Carribean Islands, and along the Gulf Coast to Texas. The west coast population extends from San Francisco Bay to Mexico. Southern populations are year-round residents. Northern populations winter in the southern part of the breeding range. The east coast population is abundant and stable, but three west coast sub-species are endangered, and have populations of < 1000 individuals (Edelman and Conway, 1998).  One endangered western subspecies, the Yuma clapper rail, is the only subspecies to inhabit primarily freshwater marshes (Meanly, 1985).

Site Fidelity

Exhibits strong fidelity to breeding locale for migrant individuals, but winter site fidelity is unknown (Edelman and Conway, 1998).

Ease of Census

Difficult. The species is solitary and nests in dense vegetation. When disturbed, the clapper rail moves quietly away rather than flushing (Meanly, 1985)..

Feeding Habits

Generalist and opportunistic, but prefers crustaceans if available. The clapper rail forages mainly by shallow probing of sediment or surface gleaning. Their diet includes small crabs, other crustaceans, slugs, insects, small mammals and birds, small fish, and eggs (Edelman and Conway, 1998).

 

Clapper Rail Contaminant Exposure Data

I.

Organochlorine Contaminants

A.

Concentrations in Adults

1.

Clapper rails (CLRA’s) were collected from several estuaries in South Carolina between 1969 and 1971, after aerial application of mirex for fire ant control (Borthwick et al., 1973). Homogenous samples of breast and upper wing muscle were analyzed for mirex. Eggs, oil glands, and fat from select locations were analyzed for mirex. Residue range of mirex in muscle tissue was ND-1.90 mg/g wet weight. Mean mirex in oil glands from Toogoodoo Creek in December 1969, March 1970, and February 1971 were 0.52, 0.29, and 0.58 mg/g respectively. Mean mirex in fat from Toogoodoo Creek in December 1970 was 1.20 mg/g. Mean mirex in CLRA eggs from Lower Ashley River in May 1970 and May 1971 were 0.08 and 0.05 mg/g respectively.

2.

One CLRA was collected in Florida in 1974 (Johnston 1976). Residues of DDE in furcular fat and oil gland were 0.14 and 0.11 mg/g wet weight respectively. Residues of S-DDT in fat and gland were 0.49 and 0.27 mg/g respectively. Dieldrin was ND in both tissues.

3.

Carcasses were collected from 6 localities in Cape May County, New Jersey in 1967 and 1973 (Klaas and Belisle, 1977). Range of geometric mean organochlorine residues was 0.20-6.3 mg/g wet weight DDE, ND-0.88 mg/g TDE, ND-0.81 mg/g DDT, and ND-0.08 mg/g dieldrin. Concentrations of all 4 contaminants were lower in 1973 for all locations. Mirex was detected at three locations in 1973, with mean residues of 0.16, 0.39, and 0.15 mg/g. Oxychlordane was detected at one location in 1973, with a mean residue of 0.01 mg/g. Mean residues of PCBs were ND for all locations in 1967. Mean residues of PCBs in 1973 ranged from 0.14 - 1.30 mg/g.

4.

One specimen was collected from the Turtle River-Brunswick Estuary Superfund site in Georgia in 1995 (Kannan et al., 1998).   Hepatic organochlorine concentrations were <0.6 ng/g wet weight HCB, 59 ng/g  Σ-DDT, <1 ng/g Σ-chlordane, and <0.07 ng/g  Σ-HCH.  In breast muscle, concentrations were <0.6 ng/g HCB, 12 ng/g Σ-DDT,  <1 ng/g Σ-chlordane, and <0.07 ng/g Σ-HCH. In the liver, concentrations of detectable PCB congeners ranged from 6.4 ng/g PCB 153 to 62 ng/g PCB 208.  In muscle, concentrations of detectable PCB congeners ranged from 0.5 ng/g PCB 144+149 to 47 ng/g PCB 199.

5.

One clapper rail was collected in the summer of 1995 from Purvis Creek, Georgia near the site of a former chloralkali facility (Kannan et al., 1999).  Concentrations of organochlorines in muscle and liver, respectively, were 12.0 and 10.2 µg/g lipid weight PCB, 0.48 and 1.44 µg/g Σ-DDT, and 0.007 and 0.009 µg/g total chlordane isomers.  HCH isomers, HCB, and PCDDs/PCDFs were not detected.

B.

Concentrations in Eggs

1.

Eggs were collected from South Carolina, Virginia, and New Jersey from 1972-73 (Klaas et al., 1980). Geometric mean DDE residues were 0.41, 0.97, and 1.3 mg/g wet weight in eggs from South Carolina, Virginia, and New Jersey respectively. Mirex was detected in 1 egg from Virginia at 0.09 mg/g, and trace levels of trans-nonachlor were found in another egg. Trace levels of trans-nonachlor were found in nine eggs from New Jersey. Mirex was detected in 5 eggs from New Jersey, with a mean residue of 0.34 mg/g. Residues of DDE were detected in 3 eggs from New Jersey, with a mean of 0.30 mg/g. Residues of DDT was detected in 1 egg from New Jersey at 0.25 mg/g. PCBs were ND at any location.

2.

Eggs were collected from several sites in San Francisco Bay, California in 1975, 1986, and 1987 (Lonzarich et al., 1992). Residues of PCB in eggs collected in 1975 ranged from 1.80 to 7.00 mg/g wet weight. Residues of PCB in eggs collected in 1986 ranged from 0.32 to 3.20 mg/g. Residues of PCB in eggs collected in 1987 ranged from 0.42 to 1.25 mg/g. Residues of DDE in eggs collected in 1975 ranged from 0.38 to 2.10 mg/g. Residues of DDE in eggs collected in 1986 ranged from 0.15 to 0.62 mg/g. Residues of DDE in eggs collected in 1987 ranged from 0.14 to 0.63 mg/g.

3.

Eggs were collected from southern California between 1986 and 1989 (Jarman et al., 1993). Geometric mean (range) residues were 3.00 mg/g wet weight (1.60-4.80) S-DDT, 0.51 mg/g (0.32-0.59) S-PCB, 0.24 mg/g (0.16-0.30) oxychlordane, 0.13 mg/g (0.08-0.18 mg/g) MC-2 (1-exo,2-endo,3-exo,4,7,8,8-heptachloro-3a,4,7,7a-tetrahydro-4,7-methanoindane), 0.005 mg/g (0.004-0.008) MC-5 (1-exo,2-endo,3-exo,4,5,7,8,8-octachloro-3a,4,7,7a-tetrahydro-4,7-methanoindane), 0.17 mg/g (0.10-0.26) trans-nonachlor, and 0.61 mg/g (0.43-0.78) S-chlordanes. Residues of trans-chlordane, cis-chlordane, and cis-nonachlor were < 0.01mg/g.

4.

In 1992, 22 failed California clapper rail eggs were collected from south San Francisco Bay, California (Schwarzbach et al., 2001). Geometric mean organochlorine concentrations were: 0.02 mg/g dieldrin, 0.01 mg/g heptachlor epoxide, 0.03 mg/g oxychlordane, 0.06 mg/g trans-nonachlor, 0.11 mg/g DDE, and 1.30 mg/g total PCB.  Total PCB concentrations ranged from 0.65-5.01 mg/g. The organochlorine concentrations detected were strongly correlated with each other. The following were not detected: toxaphene, endrin, o,p’-DDT, o,p’-DDE, o,p’-DDD, DDT, DDD, cis-nonachlor, α-chlordane, γ-chlordane, and mirex.

II.

Cholinesterase-Inhibiting Pesticides

 

No direct exposure data available

III.

Trace Elements, Metals, and Metalloids

1.

Fifty-eight CLRA’s were collected from Savannah Estuary to Little Cumberland Island, Georgia between October 1971 and September 1973 (Odom, 1975). The breast muscle of 55 specimens was analyzed for Hg. Eighteen livers, 2 beaks, 1 feather sample, 1 eggshell sample, and contents of 1 egg sample were also analyzed. Concentration range of Hg was 0.01-9.45 mg/g wet weight in breast muscle, and 0.33-8.63 mg/g in liver. Concentrations of Hg were 1.66 and 8.1 mg/g in beak, 0.17 in eggshell, and 0.20 mg/g in egg contents.

2.

Between 1974 and 1976, one clapper rail was collected from Brunswick, Georgia (Gardner et al., 1978). Mercury concentrations of 5.0 mg/g dry weight in the muscle, of which 99% was MeHg, and 19 mg/g in the liver, of which 60% was MeHg, were found.

3.

CLRA’s were collected from the polluted Brunswick Estuary and Savannah Estuary in Georgia between July, 1975 and June, 1978 (Odom, 1978). Concentration range of Hg in Savannah Estuary was 0.16-1.22 mg/g wet weight in breast muscle, and 0.53-15.0 mg/g in liver. Concentration range of Hg in Brunswick Estuary was 0.15-21.2 mg/g in breast muscle, and 0.52-57.5 mg/g in liver.

4.

CLRA’s were collected from the polluted Brunswick Estuary and Savannah Estuary and from several uncontaminated estuaries in Georgia between July, 1978 and June, 1981 (Odom, 1980). Mean concentration of Hg in Brunswick Estuary was 1.58 mg/g wet weight in breast muscle and 4.08 mg/g in liver. Mean concentration of Hg in Savannah Estuary was 0.45 mg/g in breast muscle and 0.99 mg/g in liver. Mean concentration of Hg in unpolluted estuaries was 0.39 mg/g in breast muscle and 1.00 mg/g in liver.

5.

Eggs were collected from several sites in San Francisco Bay, California and from a control site at Battery Island, North Carolina in 1975, 1986, and 1987 (Lonzarich et al., 1992). Concentration range of Se in California was 0.30-1.10 mg/g wet weight in 1986, and 0.39-1.68 mg/g in 1987. Concentration range of Se in North Carolina in 1987 was 0.20-0.31 mg/g. Concentration range of Hg in California was 0.37-0.87 mg/g in 1986, and 0.72-0.95 mg/g in 1987. Concentration range of Hg in North Carolina in 1987 was 0.12-0.33 mg/g.

6.

Eggs were collected from San Francisco Bay, California in 1991 (Schwarzbach et al., 1993). Concentration range of Hg was 0.75-1.84 mg/g wet weight. In a companion and a follow-up study, eggs were collected from north San Francisco Bay, South San Francisco Bay, and areas outside the Bay in 1986-87 and 1992 (Schwarzbach, unpubl.). In 1986-87, mean Hg was 0.73 mg/g in the north Bay, 0.55 mg/g in the south Bay, and 0.03 mg/g in light-footed clapper rail eggs from San Diego and Orange County. In 1992, mean Hg was 0.63 mg/g in the south Bay and 0.22 mg/g in Yuma clapper rail eggs from the Colorado River’s Topoc Gorge.

7.

Eight clapper rail eggs that failed to hatch were collected in southern California in 1991 (Hui et al., 2002). Arithmetic means (geometric means) and ranges of concentrations of inorganic analytes are given in µg/g, dry weight. Seal Beach (n=3); Cr 1.81 (1.73) 0.95-3.85, Cu 2.94 (2.93) 2.63-3.37, Fe 63.33 (63.33) 62.00-64.80, Mg 367.0 (364.8) 317.0-415.0, Mn 1.120 (1.12) 1.08-1.16, Mo 2.80 (2.75) 2.30-3.63, Sr 40.13 (39.98) 35.20-43.00, Zn 42.77 (42.74) 40.60-44.20.  Tijuana Slough (n=5); Cr 2.17 (1.94) 0.95-3.85, Cu 3.34 (3.30) 2.80-4.03, Fe 78.12 (73.54) 42.90-112.0, Mg 644 (614.0) 411-1020, Mn 1.42 (1.22) 0.50-2.28, Mo 3.35 (2.81) 1.000-5.76, Sr 53.88 (49.89) 33.00-99.80, Zn 42.90 (42.58) 35.50-51.30.

8.

One carcass of a Yuma clapper rail was recovered from the Salton Sea, California some time between 1988 and 1990 (Setmire et al., 1993). The carcass Se concentration was 4.80 mg/g dry weight. The B concentration was 14.0 mg/g.

9.

Between March and June 2000, clapper rail eggs were collected from a contaminated marsh, N=21 (Linden Chemicals and Plastics; LCP) and a reference marsh N=13 (Blythe Island) near Brunswick, Georgia (Rodriguez-Navarro et al., 2002). Mean concentrations of metals in eggshells presented in µg/g; LCP – Mg 1,617, Al 79, P 3,617, Mn 7, Fe 147, Cu 1.71, Zn 6.33, As 0.21, Se 0.90, Pb 0.37, Hg 0.368. Blythe Island – Mg 1,513, Al 88, P 3,473, Mn 5, Fe 159, Cu 1.37, Zn 4.80, As 0.21, Se 0.23, Hg 0.105.

 10.

Unhatched eggs were collected from nests in San Francisco Bay, California between 1991 and 1999.  Contaminants were detected at the following levels (µg/g): nd-36 Al, nd-0.6 As, nd-4.13 Ba, nd-13 Bo, nd-0.31 Cd, nd-2.06  Cr, nd-2 Pb, 0.11-2.51 Hg, nd Mo, 1.89-2.22 Se, nd-0.04 Ag, and 11.1-176 St.  

IV.

Petroleum

 

No direct exposure data available

V.

Other

1.

One clapper rail was collected in the summer of 1995 from Purvis Creek, Georgia near the site of a former chloralkali facility (Kannan et al., 1999).  Concentrations of organohalogens--extractable organic chlorine (EOCl), extractable organic bromine (EOBr), and extractable organic iodine (EOI)--were measured in the muscle and liver.  Concentrations were 14 and 47 µg/g wet weight, respectively, EOCl, and 0.14 and 0.49 µg/g EOBr.  EOI was not detected.

 

Clapper Rail Contaminant Response Data

I.

Organochlorine Contaminants

1.

CLRA’s raised from wild-harvested eggs collected from Ocean City, Maryland in 1967 were dosed with various concentrations of DDT (Van Velzen and Kreitzer, 1975). The 5-day LC50 was reported separately for males and females, and the brain, liver, and carcasses of birds fed different doses were subsequently measured for DDT, DDD, and DDE. Males were initially dosed with 2500 ppm DDT, which was incremented at 250 ppm or 500 ppm for successive doses. Females were initially dosed with 2000 ppm DDT, which was incremented at 250 ppm for successive doses. The 5-day LC50 for males was 1612 ppm and for females was 1896 ppm. Mean DDE concentrations in the brain, liver, and carcass were 4.30, 23.9, and 3.00 mg/g respectively for dead males, and 1.10, 11.2, and 5.10 mg/g respectively for surviving males. Mean DDE concentrations in the brain, liver, and carcass were 3.60, 18.9, and 3.20 mg/g respectively for dead females, and 7.00, 5.30, and 4.30 mg/g respectively for surviving females.

2.

Museum specimens of eggs were used to compare eggshell thickness between the periods 1863-1946 and 1947-1973 (Klaas et al., 1980). No significant changes in eggshell thickness were detected between the two time periods. However, museum egg specimens from Florida had significantly thinner shells than those collected between Georgia and New Jersey.

3.

In 1992, 11 California clapper rail eggs were collected from south San Francisco Bay, California (Schwarzbach et al., 2001). Mean egg thickness, 262±21 microns, was not different from pre-1932 museum eggs measured (N=27, mean value of 271±16 microns) and was not correlated with organochlorine content.

II.

Cholinesterase-Inhibiting Pesticides

 

No response data available

III.

Trace Elements, Metals, and Metalloids

1.

Between March and June 2000, clapper rail eggs were collected from a contaminated marsh, N=21 (Linden Chemicals and Plastics; LCP) and a reference marsh N=13 (Blythe Island) near Brunswick, Georgia (Rodriguez-Navarro et al., 2002). Metals and elements (Mg, Al, P, K, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Cd, Pb, Hg) were examined as causation of eggshell thickness differences, by inhibiting crystal growth, since PCBs were not measured above background concentrations. Eggshell thickness (ET, measured in mm), degree of crystal orientation (full width half maximum, FWHM, in degrees), and organic mater content (%N, in percentage) were recorded in min, max and means±SD. LCP- ET  150-190, 171±10, FWHM 16-41, 24±7, %N 1.13-0.33, 0.53±0.20, Blythe Island- ET 160-220, 183±15, FWHM 12-32, 19±5, 2.43-0.27, 0.78±0.70. Eggshells from the contaminated site were abnormally brittle, substantially thinner (7%), had a relatively higher crystal orientation, and contained anomalous microstructural attributes. Structural changes may be related to specific metal concentrations, but statistical analyses indicated that metals only explained a small portion of variation in thickness and crystal orientation.

IV.

Petroleum

 

No response data available

References for Clapper Rail

Borthwick, P.W., T.W. Duke, A.J. Wilson, Jr., J.I. Lowe, J.M. Patrick, Jr., and J.C. Oberheu. 1973. Residues in fish, wildlife, and estuaries. 1973. Pestic. Monit. J. 7:6-26.

Edelman, W.R., and C.J. Conway. 1998. Clapper rail. In A. Poole and F. Gill eds. The Birds of North America. No. 340. 32 pp.

Ehrlich, P.R., D.S. Dobkin, and D. Wheye. 1988. The Birder’s Handbook. Simon & Schuster, New York. 785 pp.

Foehrenbach, J., G. Mahmood, and D. Sullivan. 1970. DDT residues in eggs of marsh-inhabiting birds. NY Fish and Game J. 17:126-127.

Gardner, W.S., D.R. Kendall, R.R. Odom, H.L. Windom, and J.A. Stephens. 1978. The distribution of methyl mercury in a contaminated salt marsh ecosystem. Environ. Pollut. 15: 243-251.

Hui, C.A., S.L. Goodbred, D.B. Ledig, and C.A. Roberts. 2002. Inorganic analytes in light-footed clapper rail eggs, in their primary prey, and in sediment from two California salt marsh habitats. Bull. Environ. Contam. Toxicol. 68:870-877.

Klaas, E.E. and A.A. Belisle. 1977. Organochlorine pesticides and polychlorinated biphenyl residues in selected fauna from a New Jersey salt marsh--1967 vs. 1973. Pestic. Monit. J. 10:149-158.

Klaas, E.E., H.M. Ohlendorf, and E. Cromartie. 1980. Organochlorine residues and shell thickness in eggs of the clapper rail, common gallinule, purple gallinule, and limpkin (Class Aves), eastern and southern United States, 1972-74. Pestic. Monit. J. 14:90-94.

Jarman, W.M., R.J. Norstrom, M. Simon, S.A. Burns, C.A. Bacon, and B.R.T. Simoneit. 1993. Organochlorines, including chlordane compounds and their metabolites, in peregrine-falcon, prairie-falcon, and clapper-rail eggs from the USA. Environ. Pollut. 81:127-136.

Johnston, D.W. 1976. Organochlorine pesticide residues in uropygial glands and adipose tissue of wild birds. Bull. Environ. Contam. Toxicol. 16:149-155.

Kannan K., H. Nakata, R. Stafford, G. R. Masson, S. Tanabe, and J.P. Giesy.  1998.  Bioaccumulation and toxic potential of extremely hydrophobic polychlorinated biphenyl congeners in biota collected at a Superfund site contaminated with Aroclor 1268. Environ. Sci. Tech. 32:1214-1221.

Kannan K., M. Kawano, Y. Kashima, M. Matsui, and J.P. Giesy.  1999.  Extractable organohalogens (EOX) in sediment and biota collected at an estuarine marsh near a former chloralkali facility.  Environ. Sci. Tech. 33:1004-1008.

Lonzarich, D.G., T.E. Harvey, and J.E. Takekawa. 1992. Trace elements and organochlorine concentrations in california clapper rail (Rallus longirostris obsoletus) eggs. Arch. Environ. Contam. Toxicol. 23:147-153.

Odom, R.R. 1975. Mercury contamination in Georgia rails. Proceedings of the annual conference of the southeast association of game and fish commissions. 28:649-658.

Odom, R.R. 1978. Statewide wildlife investigation: mercury contamination studies. Georgia Game and Fish Div. Project Number GA. W-037-R-14 JOB 16/FIN. 15 pp.

Odom, R.R. 1980. Statewide wildlife investigation: mercury contamination investigations. Georgia Game and Fish Div. Project Number GA. W-037-R/Study 16 /FIN. 17 pp.

Rodriguez-Navarro, A.B., K.F. Gaines, C.S. Romanek and G.R. Masson. 2002. Mineralization of clapper rail eggshell from a contaminated salt marsh system. Arch. Enrivon. Contam. Toxicol. 43:449-460.

Schwarzbach, S.E. 1991. Mercury in California clapper rail eggs, invertebrate prey, and sediments from tidal wetlands in south San Francisco Bay. Conference paper abstract. Society of Environ. Toxicol. Chem. 14th Annual Meeting Abstract Book. pp.117.

Schwarzbach, S.E, J.D. Henderson, C.M. Thomas, and J.D. Albertson. 2001. Organochlorine concentrations and eggshell thickness in failed eggs of the California clapper rail from south San Francisco Bay. Condor 103: 620-624.

Schwarzbach, S.E., J.D. Albertson, and C.M. Thomas.  2006.  Effects of predation, flooding, and contamination on reproductive success of California clapper rails (Rallus longirostris obsoletus) in San Francisco Bay.  Auk 123:45-60.

Setmire, J.G., R.A. Schroeder, J.N. Densmore, S.L. Goodbred, D.J. Audet, and W.R. Radke. 1993. Detailed study of water quality, bottom sediment, and biota associated with irrigation drainage in the Salton Sea Area, California, 1988-90. U.S. Geological Survey Water Resources Investigations. Report 93-4014. Sacramento, CA. 102 pp.

Van Velzen, A., and J.F. Kretzer. 1975. The toxicity of p,p’-DDT to the clapper rail. J. Wildl. Manage. 39:305-309.

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